Nickan Research Institute Journal of Renal Injury Prevention 2345-2781 15 1 2026 03 01 C-reactive protein to albumin ratio as a predictor of contrast-induced nephropathy; a systematic review and meta-analysis e38399 e38399 10.34172/jrip.2025.38399 EN Sam Mirfendereski https://orcid.org/0000-0002-6153-5696 Mahdieh Ahmadnia https://orcid.org/0009-0004-4703-9495 Ali Hasanpour Dehkordi https://orcid.org/0000-0003-4285-8497 Journal Article 10.34172/jrip.2025.38399 2025 09 16 2025 12 10 Introduction: The C-reactive protein-to-albumin ratio (CAR) is a marker of inflammation that has been found to be more informative in assessing inflammation conditions in cardiovascular patients than the C-reactive protein (CRP) or albumin (ALB) levels only. Since inflammation has been identified as a factor causing contrast-induced nephropathy (CIN), this research seeks to establish the correlation between the CAR and the risk of CIN. Materials and Methods: This systematic review and meta-analysis was conducted according to the PRISMA protocol. The Cochrane, PubMed, ProQuest, and Web of Science databases, as well as the Google Scholar search engine, were searched with no time limit up to August 8, 2024. Data were analyzed using STATA 14 software at a significance level of P < 0.05 for all tests. Results: The findings of five reviewed studies with a total number of 1,442 participants showed a statistically significant positive correlation between CAR (OR: 2.11, 95% CI: 1.41, 3.14) and CRP (OR: 1.11, 95% CI: 1.02, 1.20), with an increase in the risk of CIN. However, no statistically significant associations were found between the patient age (OR: 1.02, 95% CI: 0.96, 1.09), albumin level (OR: 0.64, 95% CI: 0.14, 2.90), hypertension (OR: 2.12, 95% CI: 0.86, 5.21), and diabetes mellitus (OR: 0.80, 95% CI: 0.28, 2.29) variables and the risk of CIN. Conclusion: Elevated CAR and CRP are CIN risk factors that can be evaluated to provide a good prognosis of this condition. Nevertheless, albumin levels were not significantly related to the development of CIN. Registration: This study has been compiled based on the PRISMA checklist, and its protocol was registered on the PROSPERO (ID: CRD42024580053) and Research Registry (UIN: reviewregistry1874) websites.